Cross trade has absolutely nothing to do with trading between markets - don't know where you got this idea from - and it's not something you can do. If you execute on ChiX then buyer & seller are on ChiX. Sorry don't know how to make it any simpler.
XT TM means the one (same) broker has represented both the buyer & seller and reported it via ASX Tradematch. So you want to buy XYZ @ 3.2 you place your order with Comsec and you enter the queue 10th from the top, then a different Comsec customer places a sell of XYZ @ 3.2 so Comsec msatches your trade - you jump the queue and buy from the other customer and Comsec reports the trade on TradeMatch as XT TM.
